Paragonimiasis: An unusual cause of Cor pulmonale; A case report

Abstract

Paragonimiasis is a parasitic disease caused by the trematode Paragonimus. It follows ingestion of raw or improperly cooked or prickled crab and crayfish. Adult worms can survive for 20 years.

A 42-year-old rural dweller was seen at the chest unit with a three month history of cough, chest pain and haemoptysis and a ten week history of bilateral leg swelling. He recalled that his problem dated back to 18 years ago when he first had cough with rusty brown sputum and chest pain. He was treated for pulmonary tuberculosis even though sputum examination did not reveal any AAFB on two occasions. Further enquiries showed that he had enjoyed fishing and hunting for crabs in his adolescent years and ate the young crabs raw. Abnormal findings were mild central cyanosis, pitting leg and scrotal edema jugular venous pulsation was elevated with tender hepatomegaly. Sputum for ova of paragonimiasis which was positive. Packed cell volume was 55%, ESR of 15 mm in the 1st hour. Chest radiograph: patchy opacities, tubular shadowing and prominent pulmonary conus. Echocardiography showed dilated right atrium and ventricle without septal and valvular lesions. Sputum AAFB, A diagnosis of Cor pulmonale due to Paragonimiasis was made and patient treated with Praziquantel.

The patient improved markedly and repeated X-ray showed some improvement in the features. Paragonimiasis is an important tropical lung disease. The most frequent symptoms are cough and haemoptysis. The radiological features include cavities, cysts, calcified nodules all of which make differentiation from pulmonary tuberculosis difficult. In endemic areas, patients who complain of cough and haemoptysis should have their sputum examined by an experienced microbiologist for paragonimiasis.